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Low-rank matrix recovery with total generalized variation for defending adversarial examples

Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 432-445页

作者： Wen LI hengyou WANG Lianzhi HUO Qiang he Linlin CheN Zhiquan he Wing W.Y.Ng School of Science Beijing University of Civil Engineering and ArchitectureBeijing 100044China School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Guangdong Key Laboratory of Intelligent Information Processing Shenzhen 518060China Institute of Big Data Modeling and Technology Beijing University of Civil Engineering and ArchitectureBeijing 100044China

Low-rank matrix decomposition with first-order total variation(TV)regularization exhibits excellent performance in exploration of image structure.Taking advantage of its excellent performance in image denoising,we apply it to improve the robustness of deep neural networks.However,although TV regularization can improve the robustness of the model,it reduces the accuracy of normal samples due to its over-smoothing.In our work,we develop a new low-rank matrix recovery model,called LRTGV,which incorporates total generalized variation(TGV)regularization into the reweighted low-rank matrix recovery model.In the proposed model,TGV is used to better reconstruct texture information without over-smoothing.The reweighted nuclear norm and Li-norm can enhance the global structure information.Thus,the proposed LRTGV can destroy the structure of adversarial noise while re-enhancing the global structure and local texture of the image.To solve the challenging optimal model issue,we propose an algorithm based on the alternating direction method of multipliers.Experimental results show that the proposed algorithm has a certain defense capability against black-box attacks,and outperforms state-of-the-art low-rank matrix recovery methods in image restoration.

关键词： Total generalized variation Low-rank matrix Alternating direction method of multipliers Adversarial example

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Selective N-Methylation of N-Methylaniline with CO_(2) and H_(2) over Cu/In_(2)O_(3) Catalyst

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Chinese Journal of Chemistry 2024年第3期42卷 276-282页

作者： Huan Zheng Bo Qian Lin he State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China University of Chinese Academy of Sciences Beijing100049 China

N-Methylation of amines with CO_(2) and H2 is a potential approach for CO_(2) utilization because N-methylated amines can be used as solvents and organic intermediates. In_(2)O_(3)-supported Cu (Cu/In_(2)O_(3)) acts as an effective heterogeneous catalyst for N-methylation reaction of N-methylaniline (MA) with CO_(2) and H_(2),showing higher N,N-dimethylaniline (DMA) selectivity than other supported Cu catalysts. On one hand,the dispersion of Cu can be improved by the defective In_(2)O_(3) support. On the other hand,In_(2)O_(3) support is active in the dissociative adsorption of CO_(2) through C—O bond breaking. In addition,the H_(2) dissociation ability of In_(2)O_(3) can also be enhanced by Cu. The combination of Cu and In_(2)O_(3) is effective in the activation of CO_(2),the adsorption of intermediate N-methylformanilide (MFA),the hydrogenation of MFA to DMA and the prohibition of C—N bond cleavage side reactions,thereby enhancing the reaction rate of MA conversion and the selectivity to DMA.

关键词： N-Methylation CO_(2) Cu/In_(2)O_(3) Supported catalysts heterogeneous catalysis

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Operational optimization of copper flotation process based on the weighted Gaussian process regression and index-oriented adaptive differential evolution algorithm

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Chinese Journal of Chemical Engineering 2024年第2期66卷 167-179页

作者： Zhiqiang Wang Dakuo he Haotian Nie College of Information Science and Engineering Northeastern UniversityShenyang 110004China State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110004China

Concentrate copper grade(CCG)is one of the important production indicators of copper flotation processes,and keeping the CCG at the set value is of great significance to the economic benefit of copper flotation industrial processes.This paper addresses the fluctuation problem of CCG through an operational optimization method.Firstly,a density-based affinity propagationalgorithm is proposed so that more ideal working condition categories can be obtained for the complex raw ore properties.Next,a Bayesian network(BN)is applied to explore the relationship between the operational variables and the CCG.Based on the analysis results of BN,a weighted Gaussian process regression model is constructed to predict the CCG that a higher prediction accuracy can be obtained.To ensure the predicted CCG is close to the set value with a smaller magnitude of the operation adjustments and a smaller uncertainty of the prediction results,an index-oriented adaptive differential evolution(IOADE)algorithm is proposed,and the convergence performance of IOADE is superior to the traditional differential evolution and adaptive differential evolution methods.Finally,the effectiveness and feasibility of the proposed methods are verified by the experiments on a copper flotation industrial process.

关键词： Weighted Gaussian process regression Index-oriented adaptive differential evolution Operational optimization Copper flotation process

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Role of phosphorus on the biogeochemical behavior of cadmium in the contaminated soil under leaching and pot experiments

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Journal of Environmental Sciences 2024年第3期137卷 488-499页

作者： Hui Jia YifanWu Mengqi Zhang Jinhui Ye Daolin Du he Wang Institute of Environment and Ecology School of Emergency ManagementJiangsu UniversityZhenjiang 212013China School of the Environment and Safety Engineering&Institute of Environment and Ecology Jiangsu UniversityZhenjiang 212013China Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment Suzhou University of Science and TechnologySuzhou 215009China Xuzhou Medical University Affiliated HospitalXuzhou 221004China

Phosphorus(P)is involved in various biochemical reactions in plant growth,so it is beneficial to plants growing in soils contaminated by metals,including cadmium(Cd).However,few studies have reported on the mechanistic roles of P in mitigating Cd toxicity to ryegrass root,and especially in alleviating the disruption of the mitochondrial function of living cells.In this study,the physiological and biochemical mechanisms associated with ryegrass growth under various Cd and P treatments were investigated using leaching and pot systems.The concentration of Cd in soil leachates showed a significantly positive relationship with redox potential(Phe control(without P addition),the cumulative Cd content was reduced by 53.3%and 64.5%in the soil leachate with exogenous P application(20 mg/L and 80 mg/L),respectively.Notably,application of P decreased the Cd concentrations in the symplastic fractions and increased the Cd concentrations in the apoplastic fractions in root tips,which may help to alleviate Cd stress to the protoplast.Moreover,exogenous P was found to play a positive role in mitochondrial function and Ca^(2+)variation in root cells under Cd stress,which provides novel insights into the mechanisms of exogenous P in alleviating plant Cd injury.

关键词： Phosphorus Cadmium stress Protoplast Biogeochemical behavior Mitochondrial function

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Efficient and bright broadband electroluminescence based on environmentfriendly metal halide nanoclusters

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Light(Science & Applications) 2024年第4期13卷 727-737页

作者： Dingshuo Zhang Meiyi Zhu Yifan he Qingli Cao Yun Gao Hongjin Li Guochao Lu Qiaopeng Cui Yongmiao Shen Haiping he Xingliang Dai Zhizhen Ye School of Materials Science and Engineering State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University310027 HangzhouChina. Wenzhou Key Laboratory of Novel Optoelectronic and Nano Materials and Engineering Research Centre of Zhejiang Province Institute of WenzhouZhejiang University325006 WenzhouChina. Wenzhou XINXINTAIJING Tech.Co.Ltd. 325006 WenzhouChina. Department of Chemistry Zhejiang Sci-Tech University310018 HangzhouChina

Broadband electroluminescence based on environment-friendly emitters is promising for healthy lighting yet remains an unprecedented challenge to progress.The copper halide-based emitters are competitive candidates for broadband emission,but their high-performance electroluminescence shows inadequate broad emission bandwidth of less than 90 nm.here,we demonstrate efficient ultra-broadband electroluminescence from a copper halide(CuI)nanocluster single emitter prepared by a one-step solution synthesis-deposition process,through dedicated design of ligands and subtle selection of solvents.The CuI nanocluster exhibits high rigidity in the excitation state as well as dual-emissive modes of phosphorescence and temperature-activated delayed fluorescence,enabling the uniform cluster-composed film to show excellent stability and high photoluminescent efficiency.In consequence,ultra-broadband light-emitting diodes(LEDs)present nearly identical performance in an inert or air atmosphere without encapsulation and outstanding high-temperature operation performance,reaching an emission full width at half maximum(FWHM)of~120 nm,a peak external quantum efficiency of 13%,a record maximum luminance of~50,000 cd m^(−2),and an operating half-lifetime of 137 h at 100 cd m^(−2).The results highlight the potential of copper halide nanoclusters for next-generation healthy lighting.

关键词： halide cluster rigidity

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Cancer profiles in China and comparisons with the USA:a comprehensive analysis in the incidence,mortality,survival,staging,and attribution to risk factors

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Science China(Life Sciences) 2024年第1期67卷 122-131页

作者： Siyi he Changfa Xia he Li Maomao Cao Fan Yang Xinxin Yan Shaoli Zhang Yi Teng Qianru Li Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

China faces a disproportionate cancer burden to the population size and is undergoing a transition in the cancer spectrum.We extracted data in five aspects of cancer incidence,mortality,survival,staging distributions,and attribution to risk factors in China,the USA and worldwide from open-source databases.We conducted a comprehensive secondary analysis of cancer profiles in China in the above aspects,and compared cancer statistics between China and the USA.A total of 4,546,400 new cancer cases and 2,992,600 deaths occurred in China in 2020,accounting for 25.1%and 30.2%of global cases,respectively.Lifestyle-related cancers including lung cancer,colorectal cancer,and breast cancer showed an upward trend and have been the leading cancer types in China.41.6%of new cancer cases and 49.3%of cancer deaths occurred in digestive-system cancers in China,and the cancers of esophagus,nasopharynx,liver,and stomach in China accounted for over 40%of global cases.Infection-related cancers showed the highest population-attributable fractions among Chinese adults,and most cancers could be attributed to behavioral and metabolic factors.The proportions of stage I for most cancer types were much higher in the USA than in China,except for esophageal cancer(78.2%vs.41.1%).The 5-year relative survival rates in China have improved substantially during 2000–2014,whereas survival for most cancer types in the USA was significantly higher than in China,except for upper gastrointestinal cancers.Our findings suggest that although substantial progress has been made in cancer control,especially in digestive system cancers in China,there was still a considerable disparity in cancer burden between China and the USA.More robust policies on risk factors and standardized screening practices are urgently warranted to curb the cancer growth and improve the prognosis for cancer patients.

关键词： cancer burden survival rate neoplasm staging risk factors China

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Stability behavior of the Lanxi ancient flood control levee after reinforcement with upside-down hanging wells and grouting curtain

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Journal of Mountain Science 2024年第1期21卷 84-99页

作者： QIN Zipeng TIAN Yan GAO Siyuan ZHOU Jianfen he Xiaohui he Weizhong GAO Jingquan School of Water Conservancy and Environment Engineering Zhejiang University of Water Resources and Electric PowerHangzhou 310018China Department of Civil Engineering Imperial College LondonLondonSW71BFEngland Lanxi Water Affairs Bureau Lanxi 321102China Zhejiang Water Conservancy Engineering Consulting Co. LtdHangzhou 310051China

The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.

关键词： Stability analysis Multiple factors Antiseepage reinforcement Upside-down hanging well Grouting curtain Ancient levee

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β-C(sp^(3))−H chlorination of amide derivatives via photoinduced copper charge transfer catalysis

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Chinese Chemical Letters 2024年第2期35卷 361-365页

作者： Yuhang he Chao Tian Guanghui An Guangming Li Key Laboratory of Functional Inorganic Material Chemistry (MOE) School of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China

An atom economicβ-C(sp^(3))−H chlorination of amide derivatives has been developed.This mild protocol employs CuCl_(2) instead of palladium catalysts with atom-economic HCl as chlorine sources and enables the late-stage functionalization of medicine derivatives.Mechanism studies suggest a plausible visible light triggered ligand-to-metal charge transfer(LMCT)/1,4-hydrogen atom transfer(HAT)cascade.

关键词： Photoinduced copper catalysis Ligand-to-metal charge transfer 1,4-Hydrogen atom transfer β-Halogenated amide Late-stage functionalization

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A Fractional-Order Ultra-Local Model-Based Adaptive Neural Network Sliding Mode Control of n-DOF Upper-Limb Exoskeleton With Input Deadzone

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 760-781页

作者： Dingxin he HaoPing Wang Yang Tian Yida Guo the School of Automation Nanjing University of Science and TechnologyNanjing 210094China IEEE Norinco Group Institute of Navigation and Control Technology Beijing 100089China

This paper proposes an adaptive neural network sliding mode control based on fractional-order ultra-local model for n-DOF upper-limb exoskeleton in presence of uncertainties,external disturbances and input deadzone.Considering the model complexity and input deadzone,a fractional-order ultra-local model is proposed to formulate the original dynamic system for simple controller design.Firstly,the control gain of ultra-local model is considered as a constant.The fractional-order sliding mode technique is designed to stabilize the closed-loop system,while fractional-order time-delay estimation is combined with neural network to estimate the lumped disturbance.Correspondingly,a fractional-order ultra-local model-based neural network sliding mode controller(FO-NNSMC) is proposed.Secondly,to avoid disadvantageous effect of improper gain selection on the control performance,the control gain of ultra-local model is considered as an unknown parameter.Then,the Nussbaum technique is introduced into the FO-NNSMC to deal with the stability problem with unknown gain.Correspondingly,a fractional-order ultra-local model-based adaptive neural network sliding mode controller(FO-ANNSMC) is proposed.Moreover,the stability analysis of the closed-loop system with the proposed method is presented by using the Lyapunov theory.Finally,with the co-simulations on virtual prototype of 7-DOF iReHave upper-limb exoskeleton and experiments on 2-DOF upper-limb exoskeleton,the obtained compared results illustrate the effectiveness and superiority of the proposed method.

关键词： Adaptive control input deadzone model-free control n-DOF upper-limb exoskeleton neural network

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Characterization of a Novel Esterase Belonging to Family V from Marinobacter flavimaris

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Journal of Ocean University of China 2024年第1期23卷 221-232页

作者： he Jingjing ZHANG Yunhui WU Leilei WANG Yaru ZHANG he LIU Zhengang SHI Xiaochong Frontiers Science Center for Deep Ocean Multispheres and Earth System and College of Marine Life SciencesOcean University of ChinaQingdao 266003China Laboratory for Marine Ecology and Environmental Science Laoshan LaboratoryQingdao 266237China Institute of Evolution&Marine Biodiversity Ocean University of ChinaQingdao 266003China

Lipolytic enzymes have attracted enormous attentions because of their ability in ester hydrolysis,ester synthesis,transesterification and other biochemical reactions.Bacteria are important sources of lipolytic enzymes applied in industry.here,a novel lipolytic enzyme encoded by esterase gene est1347 was identified in Marinobacter flavimaris WLL162,and was purified and characterized.The lipolytic enzyme Est1347 consisted of 312 amino acid residues and a 21-amino-acids N-terminal signal peptide with a predicted molecular weight of 34.2 kDa.It belongs to family V of bacterial lipolytic enzymes based on the amino acid sequence homology analysis.Est1347 is a mesophilic and alkali-resistant enzyme with the highest activity at 45℃and pH 8.5;it is stable at temperatures below 50℃and pH 7.5–11.0.Est1347 showed a preference for middle-length chain substrate p-NPC10 and a wide range of other substrates.The Km,Vmax,Kcat and Kcat/Km values of Est1347 for p-NPC10 in pH 8.5 at 45℃were 0.9411 mmol L^(−1),1285μmol min^(−1)mg^(−1),698.91 s^(−1)and 743.65 s^(−1)(mmol L^(−1))^(−1),respectively.It is also tolerant to the metal ions,organic solvents and detergents.In conclusion,the esterase Est1347 laid a foundation for further study of bacterial lipolytic enzyme family V.

关键词： esterase Marinobacter flavimaris enzymatic properties lipolytic enzyme family V

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